There may be plot/character reasons for Radagast to be absent, but yes, there's no particular reason there couldn't be some random Rivendell elves in the background (and maybe there will be!). But this is assuming there is something akin to a formal White Council meeting in the films, and not just a couple ad-hoc discussions among the individuals who happen to be there.

I expect any White Council meeting that takes place while Thorin & Co. are in Rivendell to be just such an ad-hoc affair. Any full meeting of the Council should come later, after Gandalf leaves Bilbo and the Dwarves following the encounter with Beorn. 'Thus spake Ioreth, wise-woman of Gondor: The hands of the king are the hands of a healer, and so shall the rightful king be known.' - Gandalf the White

I mean, Galadriel and Saruman had to travel a looooong way to get to Rivendell...

Could this meeting have taken place before the start of Bilbo's adventure? Of course, any formal meeting of the Council should include more members than just the top four. 'Thus spake Ioreth, wise-woman of Gondor: The hands of the king are the hands of a healer, and so shall the rightful king be known.' - Gandalf the White